Optimising Training with Incline Treadmill Workouts: A Smart Approach to Reducing Impact Forces
In running and endurance sports, managing training load while preventing injury is critical, particularly for athletes recovering from injury or dealing with high-impact forces. Recent research has demonstrated the value of uphill running in minimizing the vertical loading rate (VLR) on the body, significantly reducing impact-related forces while maintaining the metabolic demands of flat running. This method can be a powerful tool for athletes aiming to reduce stress on bones and joints without compromising fitness gains.
Research has highlighted how running on inclines can significantly reduce the vertical loading rate (VLR) on the body, which refers to the impact forces experienced with each foot strike. By altering treadmill incline, athletes can modulate these forces while maintaining similar cardiovascular demands to flat running. This approach offers a strategic means of training that supports both injury prevention and conditioning, particularly for those prone to impact-related issues.
Key Findings
Reduction of Impact Forces: The study demonstrated that uphill running at a 5% incline could decrease VLR by 53% compared to level running, while a 10% incline reduced VLR by 63%, and a 15% incline by 73%. This reduction helps to minimize stress on bones, joints, and connective tissues without compromising workout intensity.
Energy Cost and Efficiency: Uphill running generally requires a higher energy expenditure than flat running for the same speed. However, by adjusting speeds on inclines, athletes can achieve the same metabolic workload as level running but in a shorter time. For example, running at 80% of the speed used at VO₂ max on a 5% incline matches the intensity of level running at VO₂ max.
Training Implications: Utilizing uphill intervals can provide a time-efficient workout that minimizes mechanical stress while achieving high metabolic demands. This makes it especially beneficial for athletes recovering from lower limb injuries, those seeking to avoid high-impact forces, or those in endurance sports where incline running simulates race conditions.
Lemire, M., Falbriard, M., Aminian, K. et al. Correspondence Between Values of Vertical Loading Rate and Oxygen Consumption During Inclined Running. Sports Med - Open 8, 114 (2022)
What is Vertical Loading Rate (VLR)?
VLR refers to the rate at which force is applied to the body during foot strike when running. A high VLR is often associated with increased injury risk, especially in overuse injuries such as stress fractures and plantar fasciitis. Running on flat surfaces or downhill can increase VLR, but incline running has been shown to reduce VLR by as much as 73% while maintaining the same cardiovascular and energy demands as flat running.
Why Use Incline Running?
Uphill running offers a dual benefit:
Reduced Mechanical Load: By adjusting the treadmill incline, athletes can minimize the impact forces on their lower limbs. For example, a 10% incline can reduce VLR by 63% compared to flat running, making it a safer option for those returning from bone stress injuries.
Improved Efficiency: Incline running requires higher energy expenditure, meaning athletes can achieve their target aerobic intensity at slower speeds. This allows for time-efficient workouts while avoiding excessive strain on the musculoskeletal system.
Periodized Treadmill Workouts for Injury Recovery and Performance
The following tables provide detailed uphill treadmill workouts, showing how to adjust running speeds based on your VO₂ max pace and threshold pace. These sessions are designed to maximize your aerobic fitness while minimizing loading forces, perfect for athletes in injury recovery or those looking to reduce impact stress.
Table 1: VO₂ Max Pace and Threshold Speed Ranges
This table illustrates the relationship between your VO₂ max pace and threshold pace. Threshold pace typically falls between 80-90% of your VO₂ max speed, providing a guide for managing intensity during uphill sessions.
Table 2: Uphill Treadmill Speeds Based on VO₂ Max
This table provides the treadmill speeds for three specific incline workouts (5%, 10%, and 15% grades). These speeds are tailored to your VO₂ max pace and ensure that you train at an appropriate intensity while reducing VLR.
Low Incline Session (5% Grade) – 80% of VO₂ Max Pace
This session provides a moderate reduction in impact forces and is ideal for early stages of recovery or lower-intensity endurance building.
Eg:
Speed: 80% of flat velocity at VO₂ max (e.g., 9.6 km/h for a VO₂ max speed of 12 km/h)
Session: 4-minute intervals with 2 minutes of rest between sets, maintaining speed throughout.
Purpose: Reduces VLR by approximately 53%, suitable for early conditioning or recovery-focused sessions.
Moderate Incline Session (10% Grade) – 60% of VO₂ Max Pace
This workout focuses on reducing VLR by 63%, making it excellent for athletes transitioning back to running after injury while still targeting endurance improvements.
Eg:
Speed: 60% of flat VO₂ max speed (e.g., 7.2 km/h for a VO₂ max speed of 12 km/h)
Session: 4-minute intervals with 3 minutes rest, repeated 4-6 times.
Purpose: Reduces VLR by about 63%, ideal for moderate intensity training with lower musculoskeletal impact.
High Incline Session (15% Grade) – 50% of VO₂ Max Pace
Designed for high-intensity efforts with minimal impact, this workout offers a 73% reduction in VLR and is perfect for those looking to maintain fitness while reducing mechanical stress.
Eg:
Speed: 50% of flat VO₂ max speed (e.g., 6 km/h for a VO₂ max speed of 12 km/h)
Session: Continuous uphill run for 20-30 minutes, focusing on endurance at reduced mechanical load.
Purpose: Reduces VLR by over 70%, recommended for high-intensity training while mitigating impact-related stress.
How to Incorporate Incline Running into Your Training
Incorporating these incline treadmill sessions into your training routine allows for effective aerobic conditioning while protecting your joints and bones from excessive stress. Start with lower inclines (5-10%) during early phases of recovery, and gradually progress to steeper inclines (15%) as your tolerance improves. Always listen to your body, and adjust the speed or incline as necessary to ensure a smooth recovery.
The Science Behind Incline Running
The research supporting these protocols, published in Sports Medicine - Open, demonstrates that running on inclines can significantly reduce mechanical load on the body while maintaining high energy expenditure. The study showed that increasing treadmill incline reduces the VLR by over 50% at inclines of 5% or more, with no loss of cardiovascular benefit.
By applying these evidence-based workouts, athletes can continue to train at a high level while minimizing injury risk, making incline treadmill running a valuable tool for both recovery and performance enhancement.